In this paper we propose a new image quality metric based on human visual system (HVS) called PSNR-JND. This metric is based on the values of DCT coefficients of 8x8 pixel block of an image. In particular, it assumes the same formula as the PSNR (Peak Signal-to-Noise Ratio), but it computes the MSE (Mean Squared Error) on the perceptual error calculated by dividing the DCT error by the minimum DCT coefficient able to produce a visible signal called also JND (Just Noticeable Difference) or differential threshold. The differential thresholds were experimentally calculated in order to maximise the correlation between the evaluations of the metric and the human visual system. The metric PSNR-JND has outperformed other reference based quality metrics and demonstrated high correlation with the results of subjective experiments of the database TID2008

Introduction and objective: Computer Aided Decision (CAD) systems based on Medical Imaging could support radiologists in grading Hepatocellular carcinoma (HCC) by means of Computed Tomography (CT) images, avoiding medical invasive procedures such as biopsies. The identification and characterization of Regions of Interest (ROIs) containing lesions is an important phase allowing an easier classification in two classes of HCCs. Two steps are needed for the detection of lesioned ROIs: a liver isolation in each CT slice and a lesion segmentation. Materials and methods: In our previous study, materials consisted in abdominal CT hepatic lesions of only three patients subjected to liver transplant, partial hepatectomy, or US-guided needle biopsy. In this paper, thanks to a more extensively phase of data collection, available materials impressively grew to 18 patients belonging to 2-balanced classes. Several approaches were implemented to segment the region of liver and, then, to detect the ROI of the lesions. At the end of these preprocessing phases, we extracted the same morphological features of the previous work and designed an evolutionary algorithm to optimize neural network classifiers based on different subsets of features. Results and conclusion: Tests conducted on the new ANN topologies showed a higher generalization of the average performance indices regardless of the applied training, validation and test sets, confirming both the validity and the robustness of the approach of previous study even though the limited number of patients.

Data compression is widely used in many scientific areas and in a transparent manner in various daily life activities. Lossy data compression, eg in JPEG images, leads to the loss of part of the original information but usually not essential. In this paper we present a software system for the evaluation of the quality of compressed JPEG images. This system can act on different stages of Jpeg and allow to check the resulting change in the quality and compression

Anemia is diagnosed by measuring the blood concentration of hemoglobin (Hb). In the literature, many studies have aimed to diagnose anemia with non-invasive methods, for example, estimating the pallor of the conjunctiva by means of digital images. In this way, this paper aims to identify a procedure for the automatic segmentation and optimization of conjunctiva sections. Therefore, image analysis algorithms have been applied to optimize the area of interest in terms of correlation with the estimated Hb value by blood sampling. Optimization was also possible through the study of the influence of image brightness on the correct Hb estimation by means of digital images of the conjunctiva. In conclusion, interesting experimental results were reported.

The introduction and rapid growth of social computing into educational practices has encouraged the development of the networked learning through a careful evaluation of the "social nature” of digital applications that implement interaction and collaboration among network users. This evolution is reflected in the Virtual Learning Environments (VLE) systems and supports the progress to online shared spaces, the Personal Learning Environments (PLE), environments created by placing more attention to the learner and able to support both formal and informal elements. They offer more opportunity for decision making and enable users to easily customize the curriculum. Elvis is presented in this work, an example of a system based on PLE.

La rassegna stampain molti casi rappresentaun importante strumento di lavoro. I suoi impieghi spaziano dalla valutazionedi strategie di un ente, alla informazione politica, finoall'uso didattico per la ricercasu cronaca o attualità nel panorama della stampa. Tuttavia il processo di creazione di una rassegna è molto oneroso e viene spesso delegato ad aziende specializzate. In questo articolo è presentato un sistema innovativo di ricerca e classificazione dei contenuti web denominato ICARO,basato sulle risorse giornalistiche online. ICARO permette il ritrovamento e il confronto di documenti digitali egenera una rassegna stampa tematica in maniera rapida edautomatica.

In this paper we propose a digital image quality metric based on human visual system. This metric considers the coefficients of discrete cosine transform related to each 8x8 block of an image. To perform image evaluation PQMET detects a distortion applied to the image and then selects the corresponding matrix of minimum visibility thresholds capable to produce a visible signal. Therefore it uses the information about the distortion applied, with a consequent improvement in the image quality evaluation. The experimental results show that the proposed metric achieves competitive performance with other well known metrics and outperforms them in some cases.

In this paper we propose the Electronic Multimedia Health Fascicle (EMHF), a truly new software system for the very large number of available electronic health records. It allows the physician to see at a glance the patient's clinical biometric measurements and biologic parameters, so as to be able to link any alarming physical status to his recent medical history. Web based, accessible from any mobile device, and easy to use by both physicians and patients, the system facilitates patient-medical interaction. Using the system can also promote better adherence to medical guidelines by the physicians and to medical prescriptions and advice by the patients.